Chelsea has filed an official complaint against match referee Mark Clattenburg for making racial remarks towards two of their players during their 2-3 bitter Premier League defeat to Manchester United at Stamford Bridge on Sunday.

A formal complaint has been made to the Premier League's match delegate and will be forwarded to the Football Association (FA), with the Professional Game Match Officials' Board (PGMO), the body, which represents referees, now awaiting the reports from both Clattenburg and the match delegate.

"PGMO is aware of the allegations and they are being treated with the utmost seriousness. Mark will co-operate fully and welcomes the opportunity for the facts to be established," the Telegraph quoted a PGMO spokesman, as saying.

"No further comment will be made until this matter has been properly investigated," the spokesman added.

It is understood that Chelsea will allege that one player, believed to be John Obi Mikel, has complained that Clattenburg directed a comment of a racial nature at him during the game.

The complaint of the other Chelsea player is understood to allege inappropriate language

but not of a racial nature. Mikel, who was booked for dissent during the game, is believed to have confronted Clattenburg in the referee's room after the game.

Chelsea announced that they had made their complaint around two hours after the final whistle.

"We have lodged a complaint to the Premier League match delegate with regards to inappropriate language used by the referee and directed at two of our players in two separate incidents in today's match," said a Chelsea statement.

"The match delegate will pass the complaint to the Football Association . We will make no further comment at this time," the statement added. (ANI[5])